Monomer, polymers, and ophthalmic lenses and contact lenses made by using the same

ABSTRACT

A monomer as represented by general formula (a) or (a′) below, with which a polymer having high oxygen permeability and transparency and suited to an ophthalmic lens is obtained, is provided. Suitable monomers include:  
                 
 
     wherein A is a siloxanyl group; R 1  is H or a methyl group; R 2  is a substituted group that is selected from the group consisting of alkyl groups with 1 to 20 carbon atoms that may be substituted, aryl groups with 6 to 20 carbon atoms that may be substituted and formula (c) below.

TECHNICAL FIELD

[0001] This invention relates to monomers and polymers. Said monomersand polymers are particularly suited to use for ophthalmic lenses suchas contact lenses, intraocular lenses and artificial corneas.

[0002] 1. Prior of Art

[0003] Conventionally, monomers containing silicon groups are known asmonomers for ophthalmic lenses. For example,3-[tris(trimethylsiloxy)silyl]propyl methacrylate has been widely usedas monomers for ophthalmic lenses. Polymers obtained by copolymerizing3-[tris(trimethylsiloxy)silyl]propyl methacrylate withN,N-dimethylacrylamide, which is a hydrophilic monomer, have the meritsof being transparent and of having high oxygen permeability. However,sufficient compatability is not obtained with three component copolymersin which a silicone macromer such as polydimethylsiloxane having amethacryl group in the terminal is added in order to obtain high oxygenpermeability and rubber elasticity. For this reason, when they are usedas contact lenses, for example, there are instances in which the contactlenses are turbid.

[0004] 2. Disclosure of the Invention

[0005] This invention has the objective of providing monomers andpolymers, ophthalmic lenses and contact lenses in which they are used,in which the polymers that are obtained by polymerization are of highoxygen permeability and which have sufficient compatibility inthree-component systems of silicone macromers/hydrophilic monomers.

[0006] In order to achieve the aforementioned objectives, this inventionhas the following structure.

[0007] (1) A monomer comprising a polymerizable unsaturated double bondand siloxanyl group, wherein said monomer comprises a substituted groupcontaining an ester group in a side chain.

[0008] (2) The monomer of (1) above wherein the substituted groupcontaining an ester group has an ether bond and polyalkylene glycolchain.

[0009] (3) A monomer that is represented by general formula (a) or (a′)below:

[0010] wherein A is a siloxanyl group; R¹ is H or a methyl group; R² isa substituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted, aryl groupswith 6 to 20 carbon atoms that may be substituted and formula (c) below:

[0011] wherein in formula (c), R³ is H or a methyl group and R⁴ is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted and aryl groupswith 6 to 20 carbon atoms that may be substituted; k indicates aninteger of 0 to 200.

[0012] (4) The monomer of (3) above wherein the siloxanyl group (A) informula (a) or (a′) is a substituted group as represented by formula (b)below:

[0013] wherein in formula (b), A¹ to A¹¹, independently andrespectively, are selected from H, alkyl groups of 1 to 20 carbon atomsthat may be substituted or aryl groups of 6 to 20 carbon atoms that maybe substituted; n indicates an integer of 0 to 200 and a, b and c,independently and respectively, indicate integers of 0 to 20, providedthat the case where all of n, a, b and c denote zero is to beeliminated.

[0014] (5) The monomer of (3) above wherein the siloxanyl group (A) inthe aforementioned general formula (a) or (a′) is a substituted groupthat is selected from tris(trimethylsiloxy)silyl groups,bis(trimethylsiloxy)methylsilyl groups and trimethylsiloxydimethylsilylgroups.

[0015] (6) A polymer comprising the monomer described in either of (1)or (3) above as a polymerization component.

[0016] (7) The polymer of (6) above wherein a ratio of the substitutedgroup containing an ester group and the siloxanyl group is 0.1 to 1.

[0017] (8) A polymer which is a homopolymer of the monomer described ineither (1) or (3) above.

[0018] (9) A polymer comprising the monomer described in either (1) or(3) above in a range of 10% to 80% as a polymerization component.

[0019] (10) An ophthalmic lens which comprises the polymer described in(6) above.

[0020] (11) A contact lens which comprises the polymer described in (6)above.

EMBODIMENT OF THE INVENTION

[0021] First, we shall describe the various functional groups in themonomers. The polymerizable unsaturated double bond may be any doublebond as long as it can produce polymers by radical polymerization.Examples of groups that can be used include (meth)acryloyl groups,styryl groups, benzoyl groups and vinyl groups. Of these, the use ofmethacryloyl groups is desirable from the standpoints of ease ofsynthesis and polymerizability.

[0022] The term siloxanyl group indicates a group that has at least oneSi—O—Si bond. The use of substituted groups represented by formula (b)below as the siloxanyl groups is desirable from the standpoints of easeof acquisition of raw materials and ease of synthesis.

[0023] [In formula (b), A¹ to A¹¹, independently and respectively,indicate H, alkyl groups of 1 to 20 carbon atoms that may be substitutedor aryl groups of 6 to 20 carbon atoms that may be substituted. nindicates an integer of 0 to 200 and a, b and c, independently andrespectively, indicate integers of 0 to 20, provided that the case whereall of n, a, b and c denote zero is to be eliminated.]

[0024] The substituted groups having ester groups of this invention areintroduced to mitigate the water-repellency of the monomers of thisinvention and to increase their hydrophilic properties. In addition tosimple ester groups, substituted groups having polyalkylene glycolchains and ether bonds can be cited as desirable examples.

[0025] In order to further facilitate understanding of the nature ofthis invention, we shall now describe the various substituted groups ingeneral formula (a) or (a′) more specifically.

[0026] In formula (b), which illustrates the siloxanyl groups of A, A¹to A¹¹, independently and respectively, indicate H, alkyl groups such asmethyl groups, ethyl groups, propyl groups, isopropyl groups, butylgroups, isobutyl groups, sec-butyl groups, t-butyl groups, hexyl groups,cyclohexyl groups, 2-ethylhexyl groups and octyl groups and aryl groupssuch as phenyl groups and naphthyl groups. Examples of alkyl groups andaryl groups that may be substituted can include 3-glycidoxypropylgroups, 2-hydroxyethoxypropyl groups, 3-hydroxypropyl groups,3-aminopropyl groups and fluorophenyl groups. Of these, methyl groupsare the most desirable.

[0027] In formula (b), n is an integer of 0 to 200, preferably, of 0 to50, and, more preferably, of 0 to 10. a, b and c are, respectively andindividually, integers of 0 to 20, and, preferably, a, b and c are,respectively and individually, integers of 0 to 5. When n=0, desirablecombinations of a, b and c are a=b=c=1, a=b=1 and c=0.

[0028] Of the substituted groups represented by formula (b), those thatare particularly desirable from the standpoint that they can acquiredindustrially comparatively cheaply are tris(trimethylsiloxy)silylgroups, bis(trimethylsiloxy)methylsilyl groups,trimethylsilyoxydimethylsilyl groups, polydimethylsiloxane groups,polymethylsiloxane groups and poly-co-methylsiloxane-dimethylsiloxanegroups.

[0029] In formula (a) or (a′), R² indicates substituted groups that areselected from the group consisting of alkyl groups of 1 to 20 carbonatoms that may be substituted, aryl groups of 6 to 20 carbon atoms thatmay be substituted and formula (c) below.

[0030] When R² is selected from the group consisting of alkyl groups of1 to 20 carbon atoms that may be substituted and aryl groups of 6 to 20carbon atoms that may be substituted, desirable examples include methylgroups, ethyl groups, propyl groups, butyl groups, pentyl groups, hexylgroups, heptyl groups, octyl groups, decyl groups, cyclohexyl groups,benzyl groups, phenyl groups and naphthyl groups. Of these, methylgroups, ethyl groups and phenyl groups are preferable, and methyl groupsare most preferable. When R² is selected from a group comprised ofsubstituted groups of the form of formula (c), R⁴ in formula (c)indicates substituted groups that are selected from the group consistingof alkyl groups of 1 to 20 carbon atoms that may be substituted and arylgroups of 6 to 20 carbon atoms that may be substituted. Desirableexamples include methyl groups, ethyl groups, propyl groups, butylgroups, pentyl groups, hexyl groups, heptyl groups, octyl groups, decylgroups, cyclohexyl groups, benzyl groups, phenyl groups and naphthylgroups. Of these, methyl groups, ethyl groups and phenyl groups arepreferable, and methyl groups are most preferable.

[0031] In formula (c), k indicates an integer of 0 to 200. When kincreases, the hydrophilic property becomes stronger. However, thebalance with high oxygen permeability deteriorates, for which reason itshould be 0 to 50, and, more preferably, 0 to 20, in order to obtain agood balance of physical properties.

[0032] The polymers of this invention can be obtained by polymerizingthe monomers of this invention individually and they can also beobtained by copolymerization with other monomers. There are noparticular limitations on the other monomers that are copolymerized aslong as they can be copolymerized, and monomers that have (meth)acryloylgroups, styryl groups, allyl groups, vinyl groups and otherpolymerizable carbon-carbon unsaturated bonds can be utilized.

[0033] Several examples are presented below. However, this invention isnot limited to them. One group of examples includes a hydrophilicmonomer group comprised of (meth)acrylic acid, itaconic acid, crotonicacid, vinyl benzoic acid, (meth)acrylamides such asN,N-dimethylacrylamide and N-vinyl lactams such as N-vinyl pyrrolidone.Another group of examples is a hydrophobic monomer group including alkyl(meth)acrylates such as methyl (meth)acrylate and aromatic vinylmonomers such as styrene. Further, monomers having oxygen permeabilityinclude (meth)acrylates containing fluoroalkyl groups, siliconemacromers such as polydimethylsiloxane having (meth)acryloyl groups inthe terminals and 3-[tris(trimethylsiloxy)silyl]propylmethacrylate.

[0034] The (co)polymerization ratio of monomers represented by generalformula (a) or (a′) in the polymers of this invention, in the case inwhich they do not include monomers containing silicon groups and fromthe standpoint of establishing both high oxygen permeability and highhydrophilic properties, should be 30 to 100 weight %, preferably, 40 to99 weight %, and, more preferably, 50 to 95 weight %.

[0035] In copolymerization with oxygen permeable monomers, it isdesirable that the total for the monomers of this invention and otheroxygen permeable monomers be within the range of the aforementionedcopolymerization ratio. Further, in this case, when the proportion ofsiloxanyl groups is excessively high, it is difficult to assure balancebetween wettability and oxygen permeability, for which reason, it isnecessary to set a ratio of the substituted group having ester groupsand the siloxanyl group in the polymer above a fixed value. That is, itis necessary that it be from 0.1 to 1. Values from 0.3 to 0.7 areparticularly desirable.

[0036] For the purpose of obtaining good mechanical properties and ofobtaining good resistance to disinfecting solutions and cleaningsolutions, it is desirable to use monomers having two or morecopolymerizable carbon-carbon unsaturated bonds in one molecule, in thepolymers of this invention. The copolymerization ratio of the monomershaving two or more copolymerizable carbon-carbon unsaturated bonds inone molecule should be greater than 0.1 weight %, preferably, greaterthan 0.3 weight %, and, more preferably, greater than 0.5 weight %.

[0037] The polymer of this invention may also contain ultravioletabsorbents, pigments and colorants. It may also contain ultravioletabsorbents, pigments and colorants having polymerizable groups in theform that they are copolymerized.

[0038] In order to facilitate polymerization when the polymers of thisinvention are obtained by polymerization, the addition of thermalpolymerization initiators and photopolymerization initiators of whichperoxides and azo compounds are representative is desirable. Whenthermal polymerization is performed, a substance having optimumdecomposition characteristics at the desired reaction temperature isselected and used. In general, azo initiators and peroxide initiatorshaving 10 hour half-life temperatures of 40° C. to 120° C. are suitable.Carbonyl compounds, peroxides, azo compounds, sulfur compounds, halogencompounds and metal salts can be cited as photopolymerizationinitiators. These polymerization initiators can be used individually orin mixtures and are used in quantities up to approximately 1 weight %.

[0039] A polymerization solvent can be used when the polymers of thisinvention are obtained by polymerization. Various organic and inorganicsolvents can be used as the solvents and there are no particularlimitations on them. Examples that can be cited include water, variousalcohol solvents such as methanol, ethanol, propanol, 2-propanol,butanol and tert-butanol, various aromatic hydrocarbon solvents such asbenzene, toluene and xylene, various aliphatic hydrocarbon solvents suchas hexane, heptane, octane, decane, petroleum ether, kerosene, ligroinand paraffin, various ketone solvents such as acetone, methyl ethylketone and methyl isobutyl ketone, various ester solvents such as ethylacetate, butyl acetate, methyl benzoate, dioctyl plithalate and ethyleneglycol diacetate and various glycol ether solvents such as diethylether, tetrahydrofuran, dioxane, ethylene glycol dialkyl ethers,diethylene glycol dialkyl ethers, triethylene glycol dialkyl ethers,tetraethylene glycol dialkyl ethers and polyethylene glycol dialkylethers. They can be used individually or in mixtures.

[0040] Usual methods can be used as the polymerization methods andmolding methods of the polymers of this invention. They include, forexample, a method in which they are molded into rods or plates and arethen processed to the desired shapes by cutting and processing, a moldpolymerization method and a spin cast method. As an example, we shallnow describe the case in which the polymer of this invention is obtainedby the mold polymerization method.

[0041] The monomer composition is filled into the space of two moldshaving a fixed shape. Photopolymerization or thermal polymerization isperformed and it is formed to the shape of the mold. The mold can bemade of resin, glass, ceramics or metal. In the case ofphotopolymerization, a material that is optically transparent is used,and, ordinarily, resin or glass is used. In many cases, when a polymeris manufactured, a space is formed by the two opposing molds and thespace is filled with the monomer composition. Depending on the shape ofthe mold and the properties of the monomer, a gasket may be used for thepurpose of conferring a fixed thickness on the polymer and of preventingleakage of the filled monomer composition solution. The mold into thespace of which the monomer composition is filled is then irradiated withactive light rays such as ultraviolet rays or is introduced into an ovenor a water bath or oil bath and is heated to polymerize the monomers.The two methods can also be used in combination, with thermalpolymerization being performed after photopolymerization, or,conversely, it can be photopolymerization being performed after thermalpolymerization. In the case of photopolymerization, for example, lightcontaining a large portion of ultraviolet rays is usually irradiated fora short time (ordinarily 1 hour or less) using a mercury lamp or aninsect attraction lamp as the light source. When thermal polymerizationis performed, the temperature is gradually raised from close to roomtemperature, being increased to a temperature of 60° C. to 200° C. overa period of several hours to several tens of hours. These conditions aredesirable for the purpose of maintaining the optical homogeneity andquality of the polymer and of increasing reproducibility.

[0042] The molded product in which the polymer of this invention is usedcan be subjected to modification treatments by various methods. It isdesirable to perform said modification treatment for the purpose ofincreasing surface wettability.

[0043] Specific modification methods can include electromagnetic wave(including light) irradiation, plasma irradiation, chemical vapordeposition treatments such as vaporization and sputtering, heatingtreatments, treatment with bases, treatment with acids and the use ofother suitable surface treatment agents, and combinations of thesetreatments. Of these modification procedures, treatment with bases andtreatment with acids are desirable because they are simple.

[0044] Examples of treatments with bases and treatments with acids thatcan be cited include a method in which the molded product is broughtinto contact with a basic or acidic solution and a method in which themolded product is brought into contact with a basic or acidic gas. Morespecific examples include, for example, a method in which the moldedproduct is immersed in a basic or acidic solution, a method in which abasic or acidic solution or basic or acidic gas is sprayed onto themolded product, a method in which the basic or acidic solution isapplied to the molded product with a spatula or brush and a method inwhich the basic or acidic solution is applied to the molded product by aspin coating method or a dip coating method. The method whereby greatmodifying effects can be obtained the most simply is the method in whichthe molded product is immersed in a basic or acidic solution.

[0045] There are no particular limitations on the temperature when themolded product is immersed in the basic or acidic solution. However, theprocedure is usually performed in a temperature range of −50° C. to 300°C. When workability is considered, a temperature range of −10° C. to150° C. is preferable and −5° C. to 60° C. is more preferable.

[0046] The optimum period for immersion of the molded product in thebasic or acidic solution varies depending on the temperature. Ingeneral, a period of up to 100 hours is desirable, a period of up to 24hours is more preferable and a period of up to 12 hours is mostpreferable. When contact time is too long, workability and productivitydeteriorate and there are instances in which there are such deleteriouseffects as decrease of oxygen permeability and decrease of mechanicalproperties.

[0047] The bases that can be used include alkali metal hydroxides,alkaline earth metal hydroxides, various carbonates, various borates,various phosphates, ammonia, various ammonium salts, various amines andhigh molecular weight bases such as polyethylene imines and polyvinylamines. Of these, alkali metal hydroxides are the most desirable becauseof their low cost and their great treatment effectiveness.

[0048] The acids that can be used include various inorganic acids suchas sulfuric acid, phosphoric acid, hydrochloric acid and nitric acid,various organic acids such as acetic acid, formic acid, benzoic acid andphenol and various high molecular weight acids such as polyacrylic acidsand polystyrene sulfonic acids. Of these, high molecular weight acidsare the most desirable because they have great treatment effectivenessand have little deleterious effect on other physical properties.

[0049] Various inorganic and organic solvents can be used as solvents ofthe basic and acidic solutions. For example, they can include water,various alcohols such as methanol, ethanol, propanol, 2-propanol,butanol, ethylene glycol, diethylene glycol, triethylene glycol,tetraethylene glycol, polyethylene glycol and glycerol, various aromatichydrocarbons such as benzene, toluene and xylene, various aliphatichydrocarbons such as hexane, heptane, octane, decane, petroleum ether,kerosene, ligroin and paraffin, various ketones such as acetone, methylethyl ketone and methyl isobutyl ketone, various esters such as ethylacetate, butyl acetate, methyl benzoate and dioctyl phthalate, variousethers such as diethyl ether, tetrahydrofuran, dioxane, ethylene glycoldialkyl ether, diethylene glycol dialkyl ether, triethylene glycoldialkyl ether, tetraethylene glycol dialkyl ether and polyethyleneglycol dialkyl ether, various nonprotonic polar solvents such asdimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone,dimethylimidazolidinone, hexamethyl phosphoric triamide and dimethylsulfoxide, halogen solvents such as methylene chloride, chloroform,dichloroethane, trichloroethane and trichloroethylene and freonsolvents. Of these, water is the most desirable from the standpoints ofeconomic factors, convenience of handling and chemical stability. Thesesolvents can also be used in mixtures of two or more.

[0050] The basic or acidic solution that is used in this invention mayalso contain components other than the basic or acidic substances andthe solvents.

[0051] After the molded product has been subjected to treatment withbases or acids, the basic or acidic substance can be removed by washing.

[0052] Various inorganic and organic solvents can be used as washingsolvents. For example, they can include water, various alcohols such asmethanol, ethanol, propanol, 2-propanol, butanol, ethylene glycol,diethylene glycol, triethylene glycol, tetraethylene glycol,polyethylene glycol and glycerol, various aromatic hydrocarbons such asbenzene, toluene and xylene, various aliphatic hydrocarbons such ashexane, heptane, octane, decane, petroleum ether, kerosene, ligroin andparaffin, various ketones such as acetone, methyl ethyl ketone andmethyl isobutyl ketone, various esters such as ethyl acetate, butylacetate, methyl benzoate and dioctyl phthalate, various ethers such asdiethyl ether, tetrahydrofuran, dioxane, ethylene glycol dialkyl ether,diethylene glycol dialkyl ether, triethylene glycol dialkyl ether,tetraethylene glycol dialkyl ether and polyethylene glycol dialkylether, various nonprotonic polar solvents such as dimethylformamide,dimethylacetamide, N-methyl-2-pyrrolidone, dimethylimidazolidinone,hexamethyl phosphoric triaminde and dimethyl sulfoxide, halogen solventssuch as methylene chloride, chloroform, dichloroethane, trichloroethaneand trichloroethylene and freon solvents.

[0053] Mixtures of two or more of these solvents can be used as thewashing solvent. The washing solvent may contain components other thanthe solvents, for example, inorganic salts, surfactants and detergents.

[0054] The entire molded product may be subjected to said modificationtreatment or it may be performed on only a portion of the moldedproduct, for example, the surface. When only the surface is subjected tomodification treatment, only the aqueous wetting property of the surfacecan be improved without making great changes in the physical propertiesof the molded product as a whole.

[0055] The polymers of this invention should have an oxygen permeabilitycoefficient greater than 70×10⁻¹¹ (cm²/sec)mLO₂/(mL·hPa) in terms of theoxygen permeability.

[0056] The polymers of this invention are particularly suited forophthalmic lenses such as contact lenses, intraocular lenses andartificial corneas.

EXAMPLES

[0057] We shall now describe this invention in specific terms by meansof examples. However, this invention is not limited by them.

Determination Methods

[0058] The various determinations in these examples were performed bythe methods described below.

[0059] (1) Proton Nuclear Magnetic Resonance Spectrum

[0060] Determinations were performed using a model EX270 manufactured byJEOL Ltd. Chloroform-d was used as the solvent.

[0061] (2) Gas Chromatography (GC)

[0062] A capillary column (TC-5HT) manufactured by GL Sciences, Inc. wasused with a model GC-18A manufactured by SHIMADZU CORPORATION.Determinations were made with a temperature elevation program in whichthe temperature was maintained at 100° C. for 1 minute, after which thetemperature was raised to 340° C. at a rate of 10° C./minute and thenmaintained at 340° C. for 5 minutes (introduction inlet temperature,340° C.; detection temperature, 360° C.). Helium was used as a carriergas.

[0063] (3) Oxygen Permeability Coefficient

[0064] The oxygen permeability coefficient of a sample in the shape of acontact lens was determined in water of 35° C. using a Seikaken-shikifilm oxygen permeability meter manufactured by RIKA SEIKI KOGYO Co.,Ltd.

Example 1

[0065] 40 mg (95 mmol) of a siloxanyl monomer mixture represented byformulas (d) and (d′) below:

[0066] synthesized by a method in which methacrylic acid and3-glycidoxypropylmethylbis(trimethylsiloxy)silane were reacted usingsodium methacrylate as the catalyst as described in Japanese PatentApplication Laid-Open No. 22325/1981, 14.36 g (142 mmol) oftriethylamine and 80 ml of ethyl acetate were added to a 200 mL eggplanttype distillation flask and 10.1 ml (142 mmol) of acetyl chloride wasadded dropwise at 0° C. as the mixture was being stirred. The reactionsolution was stirred for 2 hours at room temperature, after which theprecipitate was removed by filtration and ethyl acetate was added. Itwas then washed twice with a saturated sodium hydrogencarbonate solutionand once with saturated saline solution and dried with sodium sulfate.The solvent was removed with an evaporator and the liquid that wasobtained was purified by distillation under reduced pressure, and atransparent liquid was obtained. Two peaks (peak area ratio, 82/18) wereseen on the GC of the liquid that was obtained. When the molecularweights of the compounds comprising the peaks were found by GC-MS, itwas indicated that the molecular weights of the compounds comprisingthese peaks were the same. For this reason, it was confirmed that thecompounds comprising these peaks were isomers of each other. The protonnuclear magnetic resonance spectrum of the liquid was determined andanalyzed. As a result, peaks were detected in the vicinity of 0 ppm(3H), in the vicinity of 0.1 ppm (18H), in the vicinity of 0.4 ppm (2H),in the vicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.1 ppm (3H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M1) and (M1′) below.

Example 2

[0067] Synthesis was performed in the same way as in Example 1 using asiloxanyl monomer mixture represented by formulas (e) and (e′) below,instead of the siloxanyl monomer mixture (d) and (d′),

[0068] synthesized by a method in which methacrylic acid and3-glycidoxypropyltris(trimethylsiloxy)silane were reacted using sodiummethacrylate as the catalyst as described in Japanese Patent ApplicationLaid-Open No. 22325/1981. The proton nuclear magnetic resonance spectrumof the liquid that was obtained was determined and analyzed. As aresult, peaks were detected in the vicinity of 0.1 ppm (27H), in thevicinity of 0.4 ppm (2H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 2.1 ppm (3H), in thevicinity of 3.4 ppm (1H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M2) and (M2′)below. The GC peak area ratio of this mixture was 87/13.

Example 3

[0069] Synthesis was performed in the same way as in Example 1 usingpropionyl chloride instead of acetyl chloride. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0 ppm (3H), in the vicinity of 0.1 ppm (18H), in thevicinity of 0.4 ppm (2H), in the vicinity of 1.1 ppm (3H), in thevicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.3 ppm (2H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M3) and (M3′) below. The GC peak area ratio ofthis mixture was 84/16.

Example 4

[0070] Synthesis was performed in the same way as in Example 2 usingpropionyl chloride instead of acetyl chloride. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0.1 ppm (27H), in the vicinity of 0.4 ppm (2H), in thevicinity of 1.1 ppm (3H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 2.3 ppm (2H), in thevicinity of 3.4 ppm (1H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M4) and (M4′)below. The GC peak area ratio of this mixture was 86/14.

Example 5

[0071] Synthesis was performed in the same way as in Example 1 usingbutyryl chloride instead of acetyl chloride. The proton nuclear magneticresonance spectrum of the liquid that was obtained was determined andanalyzed. As a result, peaks were detected in the vicinity of 0 ppm(3H), in the vicinity of 0.1 ppm (18H), in the vicinity of 0.4 ppm (2H),in the vicinity of 0.9 ppm (3H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.7 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.3 ppm (2H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M5) and (M5′) below. The GC peak area ratio ofthis mixture was 85/15.

Example 6

[0072] Synthesis was performed in the same way as in Example 2 usingbutyryl chloride instead of acetyl chloride. The proton nuclear magneticresonance spectrum of the liquid that was obtained was determined andanalyzed. As a result, peaks were detected in the vicinity of 0.1 ppm(27H), in the vicinity of 0.4 ppm (2H), in the vicinity of 0.9 ppm (3H),in the vicinity of 1.5 ppm (2H), in the vicinity of 1.7 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 2.3 ppm (2H), in thevicinity of 3.4 ppm (1H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M6) and (M6′)below. The GC peak area ratio of this mixture was 85/15.

Examples 7

[0073] Synthesis was performed in the same way as in Example 1 usingmethoxyacetyl chloride instead of acetyl chloride. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0 ppm (3H), in the vicinity of 0.1 ppm (18H), in thevicinity of 0.4 ppm (2H), in the vicinity of 1.5 ppm (2H), in thevicinity of 1.9 ppm (3H), in the vicinity of 3.4 ppm (4H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.0 ppm (2H), in thevicinity of 4.2 ppm (1H), in the vicinity of 4.4 ppm (1H), in thevicinity of 5.2 ppm (1H), in the vicinity of 5.6 ppm (1H) and in thevicinity of 6.1 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M7) and (M7′)below. The GC peak area ratio of this mixture was 83/17.

Example 8

[0074] Synthesis was performed in the same way as in Example 2 usingmethoxyacetyl chloride instead of acetyl chloride. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0.1 ppm (27H), in the vicinity of 0.4 ppm (2H), in thevicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 3.4 ppm (4H), in the vicinity of 3.6 ppm (2H), in thevicinity of 4.0 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H) and in the vicinity of 6.1 ppm (1H). From thesefindings, it was concluded that it was a mixture of the compoundsrepresented by formulas (M8) and (M8′) below. The GC peak area ratio ofthis mixture was 87/13.

Example 9

[0075] Synthesis was performed in the same way as in Example 1 using asiloxanyl monomer mixture represented by formulas (f) and (f) below,instead of the siloxanyl monomer mixture (d) and (d′),

[0076] that was synthesized using acrylic acid and sodium acrylateinstead of methacrylic acid and sodium methacrylate by a method in whichmethacrylic acid and 3-glycidoxypropylmethylbis(trimethylsiloxy)silanewere reacted using sodium methacrylate as the catalyst as described inJapanese Patent Application Laid-Open No. 22325/1981. The proton nuclearmagnetic resonance spectrum of the liquid that was obtained wasdetermined and analyzed. As a result, peaks were detected in thevicinity of 0.1 ppm (27H), in the vicinity of 0.4 ppm (2H), in thevicinity of 1.5 ppm (2H), in the vicinity of 1.9 ppm (3H), in thevicinity of 2.1 ppm (3H), in the vicinity of 3.4 ppm (1H), in thevicinity of 3.6 ppm (2H), in the vicinity of 4.2 ppm (1H), in thevicinity of 4.4 ppm (1H), in the vicinity of 5.2 ppm (1H), in thevicinity of 5.6 ppm (1H), in the vicinity of 6.1 ppm (1H) and in thevicinity of 6.4 ppm (1H). From these findings, it was concluded that itwas a mixture of the compounds represented by formulas (M9) and (M9′)below. The GC peak area ratio of this mixture was 85/15.

Example 10

[0077] The mixture of compounds of formulas (M1) and (M1′) obtained inExample 1 (30 parts by weight), N,N-dimethylacrylamide (40 parts byweight), polydimethylsiloxane of which the terminals had beenmethacrylated (molecular weight, approximately 1,000; 30 parts byweight), triethylene glycol dimethacrylate (1 part by weight) andDarocure 1173 (CIBA Specialty Chemicals Inc.; 0.2 part by weight) weremixed and stirred. A homogeneous and transparent monomer mixture wasobtained. This monomer mixture was deaerated in an argon atmosphere. Itwas poured into a contact lens mold made of a transparent resin (poly4-methylpentene-1) in a glove box in a nitrogen atmosphere and waspolymerized by light irradiation (1 mW/cm², 10 minutes) using an insectattraction lamp, and a sample in the shape of a contact lens wasobtained.

[0078] The lens-shaped sample that was obtained was subjected tohydration treatment, after which it was immersed in a 5 weight % aqueoussolution of polyacrylic acid (molecular weight, approximately 150,000)and modification treatment was performed for 8 hours at 40° C. After themodification treatment, it was washed thoroughly with purified water andimmersed in a boric acid buffer solution (pH 7.1 to 7.3) in a vial andthe vial was hermetically sealed. Said vial was introduced into anautoclave and boiling treatment was performed for 30 minutes at 120° C.After it had cooled, the lens-shaped sample was removed from the vialand was immersed in a boric acid buffer solution (pH 7.1 to 7.3).

[0079] The sample that was obtained was transparent and not turbid. Whenthis sample was subjected to hydration treatment, its oxygenpermeability coefficient was 79×10⁻¹¹ (cm²/sec)mLO₂/(mL·hPa). Thus, ithad high transparency and high oxygen permeability.

Examples 11 to 18

[0080] The monomer mixtures obtained in Examples 2 to 9 were used andcontact lens-shaped samples were obtained by the same method as inExample 10. All of the samples that were obtained were transparent andnot turbid. The oxygen permeability coefficients [×10 ⁻¹¹(cm²/sec)mLO₂/(mL·hPa)] when these samples were subjected to hydrationtreatment are shown in Table 1 below. All of the polymers were of hightransparency and oxygen permeability. TABLE 1 Oxygen permeabilitycoefficient [×10⁻¹¹ (cm²/sec)mLO₂/(mL · hPa)] Example 11 107 Example 1278 Example 13 108 Example 14 78 Example 15 104 Example 16 75 Example 17105 Example 18 80

Comparative Examples

[0081] When a monomer mixture was prepared at the same molar ratio as inExample 10 using 3-tris(trimethylsiloxy)silylpropyl methacrylate, thesubstances did not mix sufficiently and separated from each other. Thismonomer mixture was polymerized by light irradiation in the same way asin Example 10, but a transparent contact lens-shaped sample was notobtained.

Industrial Applicability

[0082] By means of this invention, monomers are provided so that thepolymers that are obtained by polymerization are of high oxygenpermeability and transparency.

1. A monomer comprising a polymerizable unsaturated double bond and asiloxanyl group, wherein said monomer comprises a substituted grouphaving an ester group in a side chain.
 2. The monomer of claim 1 whereinthe substituted group having an ester group has an ether bond andpolyalkylene glycol chain.
 3. A monomer that is represented by generalformula (a) or (a′) below:

wherein A is a siloxanyl group; R¹ is H or a methyl group; R² is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted, aryl groupswith 6 to 20 carbon atoms that may be substituted and formula (c) below:

wherein, in formula (c), R³ is H or a methyl group and R⁴ is asubstituted group that is selected from the group consisting of alkylgroups with 1 to 20 carbon atoms that may be substituted and aryl groupswith 6 to 20 carbon atoms that may be substituted; k indicates aninteger of 0 to
 200. 4. The monomer of claim 3 wherein the siloxanylgroup (A) in formula (a) or (a′) is a substituted group as representedby formula (b) below:

wherein, in formula (b), A¹ to A¹¹, independently and respectively, areselected from H, alkyl groups of 1 to 20 carbon atoms that may besubstituted or aryl groups of 6 to 20 carbon atoms that may besubstituted; n indicates an integer of 0 to 200 and a, b and c,independently and respectively, indicate integers of 0 to 20; providedthat the case where all of n, a, b and c denote zero is to beeliminated.
 5. The monomer of claim 3 wherein the siloxanyl group (A) inthe aforementioned general formula (a) or (a′) is a substituted groupthat is selected from tris(trimethylsiloxy)silyl groups,bis(trimethylsiloxy)methylsilyl groups and trimethylsiloxydimethylsilylgroups.
 6. A polymer comprising the monomer set forth in either of claim1 or 3 as a polymerization component.
 7. The polymer of claim 6 in whicha ratio of the substituted group having an ester group and the siloxanylgroup is 0.1 to
 1. 8. A polymer which is a homopolymer of the monomerset forth in either claim 1 or
 3. 9. A polymer comprising the monomerset forth in either claim 1 or 3 in a range of 10% to 80% as apolymerization component.
 10. An ophthalmic lens which comprises thepolymer set forth in claim
 6. 11. A contact lens which comprises thepolymer set forth in claim 6.